APPLIED RADIOLOGICAL ANATOMY

Detailed explanation-1: -Muscles need the energy to produce contractions. The energy is derived from adenosine triphosphate (ATP) present in muscles. Muscles tend to contain only limited quantities of ATP. When depleted, ATP needs to be resynthesized from other sources, namely creatine phosphate (CP) and muscle glycogen.

Detailed explanation-2: -During everyday activities and light exercise, the mitochondria of muscle fibers produce ATP in a process called aerobic respiration. Aerobic respiration requires the presence of oxygen to break down food energy (usually glucose and fat) to generate ATP for muscle contractions.